Die removing device



Jan.-7, 1947. A, BQLDUC 2,413,943

DIE REMOVING DEVICE FledJuly l13, 1944 Patented Jan. 7, 1947 UNITEDSTATES PATENT orlucr.N

DIE REMOVING DEVICE Albert Bolduc, Detroit, Mich. Application July 13, 1944, Serial No. `544,792

. 8 Claims. 1

The invention relates generally to dies adapted to cooperate with punches for perforating sheet metal or the like, and it has particular relation to a device for removing dies that are press tted in place.

In connection with apparatus for perforating sheet metal or the like, it is conventional to use a female die element and a punch, and these are respectively anchored on relatively movable parts of the machine or apparatus. With respect to the punch in particular, it is usual to have the punch releasably mounted so that one punch may be substituted for another, and one form of releasable connecting means comprises a springpressed ball which is adapted to seat in a groove or recess in the punch. When it is desired to remove the punch, it is only necessary to move the ball out of the recess and then the punch may be withdrawn.

The same type of releasable connection may be employed for holding the female die in place, but in many instances such connections are Ilot used. Instead of using this type of connection, the female die is press-fitted in an opening in a die-holding element, and then when it becomes necessary to remove the die, the holding element must be removed and then the die is pushed out of its opening by any kind of suitable pushing instrument powerful enough for this purpose.

This necessarily requires `time and effort.

One object of the present invention is to provide a device for removing the female die from its holding element without requiring removal of the latter, so as thereby to save considerable time and effort formerly required in removing the die.

Another object of the invention is to provide an improved device for removing the female die which can be substituted for the punch element and then used as part of the machine for removing the female die during the withdrawing movement of the punch support. f

And, in general, it is an object of the invention to provide a device which maybe quickly and easily used for removing the female die without requiring removal of the holding element therefor.

Other objects oi the invention will become apparent from the following specification, from the drawing relating thereto, and from the claims hereinafter set forth.

For a better understanding of the invention, reference may be had `to the drawing, wherein:

Figure l is a vertical view, partly in cross secing to one form of the invention.

Fig. 2 is a partial view of the apparatus shown by Fig. l, illustrating the parts at a different stage in the die-withdrawing operation.

Fig. 3 is a cross-sectional View taken substantially along the line 3-3 of Fig. l.

Fig. 4 is a cross-sectional view taken substantially along the line 4-4 of Fig. 1.

Referring to Fig. 1, the mechanism illustrated comprises an upper `platen l0 having a punch holder or block ll which is secured by machine screws i2 to the platen. The block or holder H has an opening I4 which is adapted to receive'a punch, not shown, and for releasacly holding the punch in position a spring-pressed ball device is employed, This device comprises a ball I5 movable in an opening or bore IS in the block and which is normally urged towards the opening M by a spring Il. The ball engages a groove or recess in the punch, and upon upward movement of the punch the ball through a wedging action prevents the punch from being pulled out. For the purpose of pushing the hall upwardly when the punch is to he removed, a pin may be moved upwardly through a small opening I8 in the bottom of bore it. This type of punch holding device is disclosed in Richard Patent No. 1,621,811. The lower part of the mechanism comp-rises a base 26 having a clock 2l releasably fastened by devices 22 and a die block 24 fastened by machine screws 25 to the block 2l. The female die is indicated at .25, and is sumciently press-iitted in an opening 27 inthe block 25 that normally it will be removed by any forces occurring during withdrawal of the punch. It is to be noted that the die, as shown, has an opening lithrough which the punch operates, and that below this opening a larger diameter 29 is provided and that at the junction of the` two diameters a slightly rounded annular shoulder 3G is present.

The device constructed according to the present invention comprises a sleeve 35 having a recess 3S for engagement with the ball l5, so that the sleeve may be inserted in place of the punch. A

second part of the device comprises a pin il which has an axial groove or slot 39 at its upper Vend and a circumferen-tially extending groove t!) drawn past the pin 4I However, when the pin 38 has been inserted, as seen in Fig, 2, and then is turned, the pin 4| becomes interlocked with the groove 40, as shown in Fig, 3, and then the pin 38 is held in the sleeve.

'I'he lower end of the pin 38 has a frustoconical head 45 terminating in a cylindrical wall 46 which is slightly smaller than the opening 28 in the female die, so that it may readily be moved through it. Between the end of the sleeve 35 and the frusto-conical surface on head 45, a split ring 41 is provided, and this ring is so arranged and is of such resilient character that it normally is slightly larger in outer diameter than the die opening 28. Also, in its normal condition, its inner diameter is slightly smaller than the outer diameter of the sleeve 35 and smaller than the cylindrical surface 46, so that it cannot slide upwardly over the sleeve or downwardly over the .head 45.

With the sleeve 35 and pin 38 attached to the upper block Il, the upper platen l is allowed lto move downwardly, and during this operation the head 45 on pin 38 moves downwardly through the opening 28 in the die 26, and the split ring 41 contracts as it moves into the o-pening 28. As soon, however, as the ring passes completely through the opening 28, its inherent spring action causes it to expand again, and then it assumes a position in contact with the shoulder 38, as seen in Fig. 1. Now as the platen I0 is moved up wardly, the split ring 41 becomes wedged between the shoulder 30 and the frusto-conical surface of head 45, and as a result the female die 26 becomes positively vinterlocked with the pin 38. Further upward movement of the platen l0 now causes the pin 38 to pull the female die 26 out of its opening, and this will occur even though the die is strongly press-fitted in the opening.

As soon as the die is withdrawn, the sleeve and pin 38 may be removed from the block I I and then the pin may be removed from the sleeve 35, and this allows the die 26 to be separated from the pin. It is evident that by turning the pin 38 relative tothe sleeve 35, the pin may be pulled out of the sleeve and hence pulled out of the die that has been removed, and then the split ring will fall out of the die opening.

It might be noted that the ring 41, as well as other parts of the device, may be constructed of metal suitable for the purpose, and that in particular the head will be sufficiently hard alone` with the ring that the female die will be positively removed. Any suitable spring wire or machined spring steel ring may be used, as will be evident to those skilled in the art.

Although only one form of the invention has been illustrated and described in detail, it will be apparent to those skilled in the art that various modifications may be made without departing from the scope of the appended claims.

What is claimed is:

1. A device for use in removing a die element having a die aperture from the opening in a holder in a metal punching machine having a reciprocable punch retainer, a punch, and releasable means to lock the punch in the retainer, wherein the device comprises shank means adapted to be inserted into the die aperture, means on the insertable end of the shank means which is radially expansible to engage the die element in order to remove the latter from the holder when the shank means is withdrawn, and means on the other end of the shank means adapting the latter to be connected to the retainer and releasably locked thereto in place of the punch, whereby a withdrawing movement of fthe retainer through operation of the machine may be used to remove the die.

2. In a machine having an apertured die held in the opening in a holder and a reciprocatory member adapted to carry a punch co-operable with the die, a device for removing the die from the holder and comprising shank means adapted to be connected at one end to the member in place of the punch, and means on the other end of the shank means adapted to enter the die aperture and automatically to expand after insertion so as to engage the die and withdraw the latter when the member is moved away from the die holder.

3. In a machine having an apertured die held in the opening in a holder and a reciprocatory member adapted to carry a punch co-operable with the die, a device for removing the die from the holder and comprising shank means adapted to be connected at one end to the member in place of the punch, and means on the other end of the shank means adapted to rst radially contract and enter the die aperture as the member moves toward the holder and then to expand radally to engage the die and Iinally to withdraw the die from the holder upon a reverse movement of the member.

4. In a machine having a die holder and an apertured die held in an opening in the holder, shank means insertable endwise into the die aperture, means on the insertable end of the shank means adapted to enter the die aperture and then automatically expand radially to engage the die, and a member connected to the other end of the shank means and which is reciprocatory towards and from the die in order rst to move the shank means into the die aperture and then upon reverse movement to withdraw the die from the holder.

5. A device for pulling a die element out of a holder wherein the element has a die opening which terminates inwardly in a, surface of larger diameter, which comprises a shank adapted to be inserted into the opening, an enlarged head on the insertable end of the shank and which has a conical surface merging into the shank body, a fixed collar on the shank adjacent the smaller end of the conical surface, and a resilient radially expansible and contractible ring element slidable on the shank between the conical surface and the fixed collar and which is capable of sliding between such surface and collar when the shank is inserted into the die opening so as to permit the element to be moved by the collar and to radially contract about the shank as the element is moved through the opening by the collar and to expand and be anchored against the conical surface when the shank is moved in the reverse direction.

6. A device for pulling a die element out of a holder wherein the element has a die opening which terminates inwardly in a surface of larger diameter, which comprises a shank adapted to be inserted into the opening, an enlarged head on the insertable end of the shank and which has a surface of reduced diameter next to the shank body, a fixed annular collar on the shank adjacent the surface of reduced diameter, and a resilient radially expansible and contractible ring element slidable on the shank between the collar and said surface of reduced diameter and which is capable of sliding between such surface and collar when the shank is inserted into the die opening so as to permit the element to move towards the collar and to radially contract about the shank as the element is moved through the opening by the collar and to be expanded and anchored against the head when the shank is moved in the reverse direction.

7. A device for pulling a die element out of a holder wherein the element has a die opening which terminates inwardy in a surface of larger diameter, which comprises a shank adapted to be inserted into the opening, an enlarged head on the insertable end of theV shank, xed shoulder abutment means on the shank adjacent the head but spaced therefrom, and a resilient radially expansible and contractible ring element on the shank between the head and abutment means and having an axial length substantially less than the distance between the head and abutment means so that the element can move along the shank, the abutment means being adapted to force and simultaneously cause contraction of the element through the die opening when the shank is in- 6 which terminates inwardly in a surface of larger diameter, which comprises a shank adapted to be inserted into the opening, an enlarged head on the insertable end of the shank, xed shoulder abutment means on the shank adjacent the head but spaced therefrom, and a resilient radially expansible and contractible ring element on the shank between the head and abutment means and having an axial length substantially less than the distance between the head and abutment means so that the element can move along the shank, the abutment means being adapted to force and simultaneously cause contraction of the element through the die opening when the shank is inserted into the opening and the head being adapted to anchor against the element when the shank is reversely moved and the element has ex- `banded against the die surface of larger diameter, said ring element having its outer peripheral surface next to the head sloping to smaller diametrical dimensions so as to cause the element to contract into the die opening when the sloping surface is pressed axially against the edge of the opening.

ALBERT BOLDUC. 

